In a terminal device, for example, a mobile phone or a tablet computer, a sound unit of a loudspeaker is usually disposed inside the terminal device and generates sound to outside from the terminal device via a sound channel A dust cloth usually covers a position of a sound outlet hole to prevent sound quality from being affected by dust in the environment from entering an interior of the terminal device via the sound channel. However, when the dust cloth is used, the dust is easily deposited on the dust cloth, so that the area of the sound outlet hole of the sound channel is decreased. Accordingly, volume of the loudspeaker is small, and even noise occurs.
In the prior art, a user needs to clean the dust cloth at the position of the sound outlet hole manually. In special circumstances, it is necessary to take the terminal device to a service station, where the dust on the dust cloth may be removed manually only when the terminal device is disassembled. As a result, it is not convenient to remove the dust in the sound outlet hole of the loudspeaker.